Replace the Telematics Emergency Backup Battery

The Kia Rio (2011–2018) is equipped with a telematics control unit (TCU) that includes an emergency backup battery. This battery ensures features like eCall and SOS functions remain active for a short time even if the main vehicle battery is disconnected or fails. Over time, the backup battery loses capacity and may need replacement.

When to Replace

• After several years of use (typical lifespan 5–8 years).
• If you see a telematics fault warning on the dashboard.
• If eCall or SOS functions no longer operate correctly.

Location of the TCU

• The telematics unit is mounted behind the centre dashboard, directly behind the audio head unit or infotainment display.
• To reach it, remove the centre vent trim, hazard switch, and audio or display unit.

Replacement Procedure

1. Switch ignition OFF and disconnect the vehicle battery negative terminal.
2. Remove the instrument cluster trim and centre dashboard vent.
3. Disconnect the hazard warning switch connector.
4. Remove the audio head unit or infotainment display to access the TCU.
5. Unplug the telematics unit connectors and remove the unit.
6. Open the unit cover to access the emergency backup battery.
7. Remove the old battery and install the new one in the same orientation.
8. Reassemble the TCU, reconnect wiring, and refit the dashboard components.
9. Reconnect the main battery and test eCall functions if equipped.

Maintenance Notes

• Dispose of the old lithium backup battery at a certified recycling centre.
• Always replace with the same type and voltage rating for safe operation.
• Low voltage during replacement can trigger error messages — ensure the main battery is fully charged before reconnection.